The present invention belongs, in a general way, to the technological sector of equipment for psychometrics, used for performing measurements in the mass of grains (6) stored in horizontal and vertical silos (also known as a grain storage device (7)), and refers, more specifically to a new conception applied to a pendulum type measurer (1) that is hung on steel cables (8) and immersed in the grains mass 6, measuring the temperature, relative humidity, and their dew point temperature.
The state of art of this technological sector is made of thermometry temperature sensors that can be based on the thermocouple principle or other conventional ones, positioned inside a pendulum of resistant material held by two steel cables (9), immersed in the mass of grain to measure the temperature on different points of this mass.
The conventional sensors, already comprised by the state of technique, measure the temperature inside a cable on a first moment, suffering interferences of intractable convections, afterwards measuring, through conduction and heat transfer, the temperature of the grains that are in contact with the external surface of the pendulum. This measured temperature refers to a small portion of grains (approximately 0.2 kg), because the grains present a high thermal insulation, as mentioned in different technical literatures, one centimeter thickness of a corn grain (1 cm) is equivalent to a concrete wall of twelve centimeters (12 cm). Because of this characteristic inherent to grains, we have an approximate measurement of their temperature, which makes the storage system a high risk process, subject to irreversible losses of dry matter due to the attack of fungi, insects, and bacteria.